1. Field of the Invention
The present invention is directed to a medical device which interacts with the body of a patient for stimulation and/or monitoring a physiological function, wherein the interaction is defined by control electronics on the basis of a parameter set which can be fetched from a memory.
2. Description of the Prior Art
Electromedical therapy devices for electrical stimulation of muscle tissue, such as heart pacemakers, are known which interact with the body of the patient on the basis of a parameter set which is stored in a memory. Such known pacemakers include means for detecting spontaneous heart beats and means for stimulating heart muscle activity. Control electronics activates the means for stimulation to generate electrical stimulation pulses in the absence of a spontaneous heartbeat, generally so that the pacing rate does not fall below a defined, usually variable, heartbeat rate. The interaction of the pacemaker with the body of the patient can be influenced by data, known as a "parameter set", which can be stored in a memory in the pacemaker and can be fetched with the control electronics. Such data relate to the heartbeat rate which cannot be downwardly transgressed, the sensitivity of the means for detection, and the energy content of the stimulation pulses. Usually it is possible to modify the parameter set in totality, or with respect to individual data elements. In implantable pacemakers, this is accomplished in a non-invasive manner using an external programming device operating with a telemetry circuit. Such an operation is known as programming, or reprogramming. Programming or reprogramming is normally reserved for the attending physician. Because the patient only visits the attending physical between relatively long time intervals, the physical must select the data of the parameter set so as to enable a sufficient effectiveness of the heart pacemaker for the greatest requirements of the patient and for the greatest range of situations. In the best case, the programmed parameter set thus represents a successful compromise. Under these conditions, there is the need to be able to adapt the parameter set to the momentary requirements of the patient in a simple way.